If I'm in a retreat-battle, I've usually screwed up somewhere. I don't make a habit of using the "fake retreat" option because I'm not keen on gaming the system, so to speak. It does give an advantage in some instances.
If it were to go the way of the dodo, I don't think I'd fret about it. Giving the option to sacrifice a ship is kind of like auto-resolve: I'm guaranteed to lose something but if I retreat-battle, I might be able to save everything. Alternatively, I could lose everything! There's just a sour taste in automatically losing multiple ships.
I do kind of like the "rear guard" option suggested by intrinsic_parity, though instead of a timer, I just think the rear-guard ships should start closer to the bottom of the map while the non-rear guard ships start closer to the middle. It could be used as the "fake retreat" option but since you're deploying your whole fleet, it would be CR prohibitive to do so. Anyways, it allows your (designated) fighting ships to stall while the civilian/other ships make a getaway.